In the transportation of perishable products such as fruits and vegetables, the produce is normally packed onto pallets and which are then placed in the cargo space of a refrigerated enclosure such as a truck trailer or container. Studies show that, even though the cargo units are refrigerated, outside weather conditions can produce adverse effects on the cargo. These studies show that produce in direct contact with the walls of the cargo space is prone to damage and/or shorter shelf life. It is therefore desirable for none of the cargo to be in contact with the walls of the cargo space which act as a conductor for outside weather conditions. Hence, the practice of "centerloading" was developed which in the transporting of such produce refers to placing the cargo in the center of the cargo space, thus leaving a space between between the walls of the cargo space and the cargo and in so doing allowing for maximum refrigerated air circulation. After placing the cargo in the cargo space, it is thus necessary to support the cargo in the cargo space to prevent damage to the produce due to heating or freezing if the cargo comes into into contact with the walls of the cargo space and/or the shifting of the cargo during transportation.
"Dunnage bags", large inflatable bags often made of paper with an air tight plastic liner, have been used to prevent the movement of cargo during transportation. These bags are placed in the voids between the cargo and the walls of the cargo and then inflated. When the cargo arrives at its destination and prior to unloading, the bags are punctured and discarded. Applying the concept of centerloading, however, leaves more voids as there needs to be a space between all of the cargo and all of the walls of the cargo space. Thus, more dunnage bags are needed resulting in a drastic increase in shipping costs.
U.S. Pat. No. 4,591,519 to Liebel discloses an airbag for bracing made of a stiff paperboard having good vertical stiffness when uninflated.
U.S. Pat. No. 5,042,663 to Heinrick discloses joinable inflatable bladders for packaging.
U.S. Pat. No. 5,288,188 to Vanes discloses a dunnage bag constructed of welded rectangular sheets.
U.S. Pat. No. 4,553,887 to Reeves discloses a dunnage bag made of triangular sheets of kraft paper lined with polyethylene.
U.S. Pat. No. 4,040,526 to Baxter et al discloses a dunnage bag including a bladder and reinforcing sheets enclosing the bladder.
U.S. Pat. No. 4,145,973 to Baxter discloses a dunnage bag provided with an adhesive strip for attaching the uninflated bag to the surface against which it will bear when inflated.
U.S. Pat. No. 4,366,977 to Davis et al discloses a partition for dividing the compartment of a cargo transporter and made of tube sections.
U.S. Pat. No. 5,372,396 to Nahmen discloses a cargo bed liner with side panels pivotally attached.
U.S. Pat. No. 5,437,301 to Ramsey discloses a valve especially adapted for use with dunnage bags having an actuator which, in one position is spring loaded to permit entry but not escape of compressed air into the bag for inflation and is rotatable to another position where it permits air to escape to deflate the bag.
The bags disclosed in the prior art do no ameliorate problems associated with centerloading cargo in that some of the voids created by centerloading are so large that the cost of a bag filling the large void would be excessive.
The practice of puncturing a disposable bag to release air after use was adopted as being more cost effective than use of bags disclosed in the prior art in terms of the cost of the bag and the convenience in releasing the air quickly after use. None of the valves disclosed in the cited art presently used to admit air into the bags provide for fast release of the air.
Rigid collapsible braces have been disclosed for supporting cargo in cargo space. For example, U.S. Pat. No. 4,236,854 discloses a brace having side rails and extensible side arms.
U.S. Pat. No. 4,473,331 to Wisecarver discloses a foot assembly and extensible element with lever locking member.
U.S. Pat. No. 5,181,815 to Haberkorn discloses a collapsible bracing structure and rotatable latches for releasing.
U.S. Pat. No. 3,665,638 to James discloses a load brace with selectable fixed positions.
None of the disclosed braces provide the convenience of use, versatility of application, and economy of construction of the brace of the present invention.